Remember those slender gleaming spikes Keanu Reeves and pals jacked into the backs of their noggins to go virtual-reality tripping in The Matrix? That’s certainly an image: prong-to-brain networking, your neurons serviced by skewer.

But then the movies — what can you do? The future of brain-machine interfaces may be less, umm, visible if cutting-edge research by scientists at the University of California Berkeley proves viable.

One of the biggest challenges for brain-machine interfaces (BMI) is how to create one you could use indefinitely (like for a lifetime). Even in The Matrix, connecting to the cloud seems awfully inconvenient: sit back in a chair, stab yourself in the skull. Existing real-world BMI systems are clumsier still. As KurzweilAI notes: “Current BMI systems are also limited to several hundred implantable recording sites, they generate tissue responses around the implanted electrodes that degrade recording performance over time, and are limited to months to a few years.”

What if, instead, we built entire armies of tiny dust-sized sensor nodes that could be implanted in the brain (though not autonomously — this isn’t colonize-your-brain-stem time yet) to facilitate communication of whatever sort, in this case keeping high-res tabs on neural signals and relaying data back to aggregation devices via ultrasound?

Here’s how it might work: First you pop through the skull and the brain’s dura (the membrane surrounding the brain), dipping into the brain’s neural sea itself, roughly two millimeters down, where you position thousands of low-powered CMOS chips (the “neural dust,” each as tiny as millionths of a meter) to begin capturing neural signals using electrodes and piezoelectric sensors, which convert the data to ultrasonic signals. Those signals are then picked up by a sub-dural transceiver (sitting just above the “dust” chips and simultaneously powering them ultrasonically), which relays the data to an external transceiver resting just outside the skull (ASIC, memory, battery, long-range transmitter), which in turn communicates wirelessly with whatever computing device.

Like most futurist notions, this one hasn’t been tested yet — it’s just a formal proposal — but it’s another fascinating glimpse into where we might be headed, bypassing clumsy literal BMI head-jacks for micro-scale interfaces that would link us, wire-free, to future galaxies of virtual information.